A product manager spent months working in dental practices to bring AI to small businesses. Then a16z led its $35 million round
The founder spent months working in dental practices, then personally set up the first 100 customers. Customers told investors its greatest value was recovering revenue they had been missing.
- Before a16z invested $35 million in the company, its founder spent months working in dental practices. His daily job was manually entering hundreds of insurance payments into their systems.
- Half of all AI agent activity is software engineering. Healthcare accounts for just 1%. That number is easy to misread.
- What customers valued most was not quite what the founder had pitched.
A product manager went to work in dental practices
On June 3, 2026, a16z announced that it had led a $35 million Series A in Lassie. The same day, it published the founder's account in its own outlet. The funding is not the real story. What makes this unusual is the level of operating detail: 700 US dental practices across 49 states and more than $10 million in annualized revenue. It also lays out, with unusual specificity, how to break into a vertical market. The playbook is deliberately unglamorous—and easy to copy.
The story began with a casual conversation. Steijn Pelle had moved from Amsterdam to San Francisco and worked as an early product manager at Robinhood. One day, his own dentist explained how the practice operated. Pelle was stunned: the dentist and his team spent 200 hours every month on administrative paperwork.
That is a full-time employee doing nothing but paperwork for an entire month—2,400 hours a year.
Nor was this an isolated case. Roughly 500,000 medical practices across the US face the same problem. Each spends about $200,000 a year on administrative roles that owners struggle to fill, much less retain.
After leaving Robinhood, Pelle took a real nine-to-five job for several months—first at a dental practice in Menlo Park, then at a gastroenterology practice in Scranton.
He compared himself to Jim Halpert from The Office. A typical day began by downloading a huge PDF from an insurer's website containing hundreds of payments. He would spend the next several hours entering every payment into the practice management system. Then he would print a 40-page list of hundreds of patients the system said were due for billing, check each balance, and generate the bills one by one.
Matching payments to insurance claims takes 200 hours a month
"Administrative paperwork" is too vague to explain what the AI actually took over. Money moves through a US dental practice along the path below. Pelle's account only sketches the beginning; we reconstructed the full workflow from public sources.
Practice management system (PMS)
The practice's core system. It serves as both the clinical record and the ledger, tracking who received care, which procedures were performed, how much was paid, and what remains outstanding.
Insurance claim
After treating a patient, the practice submits a request for payment to the insurer, listing the procedures performed and the amount owed under the contract.
Claims clearinghouse
An intermediary between practices and insurers. It converts claims from each practice's format into the format each insurer accepts. Think of the clearing layer behind interbank transfers: when the two sides do not speak the same language, someone has to translate.
Electronic funds transfer (EFT)
The insurer deposits money directly into the practice's bank account, replacing the paper checks traditionally sent by mail.
Explanation of Benefits (EOB) / Electronic Remittance Advice (ERA)
An EOB explains coverage and payment to the patient. An ERA is the electronic payment detail an insurer sends to the practice, showing which patients and procedures a payment covers, how much was paid, and what was denied. The drawer labeled "E.O.B.s" in the photo above held these records.
Here is how a dental bill moves through that system:
The patient receives care, and the practice records each procedure in its PMS
Fillings, extractions, and X-rays each have a code and a price
The practice submits an insurance claim through a claims clearinghouse
The clearinghouse converts it into the insurer's accepted format
The insurer reviews the claim, pays, and sends payment details
Payment arrives by EFT or paper check; the EOB or ERA explains what was paid or denied
The incoming payment is matched to the claims originally submitted
Each reconciled item is then posted back to the PMS
Manual bottleneckIf insurance pays only part, the remainder is calculated and billed to the patient
That 40-page list was produced at this stage
Denied and underpaid claims are identified and appealed individually
Missed claims become lost revenue
Also manualThe payment workflow at a US dental practice, reconstructed from public sources. Step 4 consumes most of those 200 hours. Step 6 is where revenue can disappear outright.
Most of those "200 hours of administrative work" are spent manually matching payments to insurance claims.
After speaking with hundreds of small-business owners, Pelle was struck by how similar they were. First, most were reluctant operators. Doctors want to treat patients, plumbers want to fix toilets, and nail technicians want to do nails. Paperwork is the last thing they want to touch, but if nobody else can do it, they have to. Second, every small business relies on the same basic tasks: enter data into a system, move data between systems, communicate with customers, and complete transactions.
He offered a specific example: Dr. Ed Zuckerberg, Mark Zuckerberg's father, who opened a dental practice in Dobbs Ferry, New York. After a full day at work, dinner with his family, and putting the children to bed, he would still go downstairs to his home office at 11 p.m. to handle paperwork.
Software has not eliminated this work. It has merely rearranged it. You get a dashboard, a queue, a form, and perhaps a better place to click. But someone still has to click.
Steijn Pelle · a16z News · 2026-06-03
AI changes that. For the first time, software can understand messy context, operate across systems, and finish the job. So the founders asked whether they could build software that lets a small business run itself.
Half of AI agent activity is software engineering. Healthcare accounts for just 1%
If AI is already so capable, why are humans still typing in every payment? Public data offers an answer. In February 2026, Anthropic analyzed nearly 1 million agent tool calls on its API and classified them by industry.
Share of agent tool calls (%) · Sample: 998,481
Data from Figure 6 of Anthropic's Measuring Agent Autonomy, published in February 2026. The metric is agent tool calls made through Anthropic's public API. We redrew the original chart without changing any values.
Half of all agent activity is software engineering. The other half is spread across 16 industries, none above 9%. Healthcare accounts for 1.0%; legal work, 0.9%.
Those small numbers are easy to misread. They point to markets that have barely been tapped. Healthcare AI is still in its infancy.
Anthropic offered a more practical explanation in a footnote to the study. Software moved first because code is easy to verify: run it, and you can see whether it works. Errors are also easier to detect. In law, healthcare, and finance, checking whether an agent performed correctly often requires as much professional expertise as doing the work itself. Trust therefore takes much longer to build.
Dental practices rely on dozens of systems that fail without warning
If the market is so open, why has nobody solved it? Pelle identifies three barriers. The second is the most concrete.
First: "mostly right" is not good enough
Owners must trust that claims were filed correctly, patient messages were accurate, and insurer responses were properly posted. Every entry involves money and regulated, sensitive medical information.
Second: it must handle dozens of temperamental external systems at once
A dental practice connects to dozens of insurer portals, several claims clearinghouses, a practice management system, and a bank account. There is no shared standard or central coordinator.
Each works differently—and fails without warning.
Steijn Pelle · a16z News · 2026-06-03
Illustration by this site. Taking over a practice's collections means supporting every system in this ring, even though each connection fails at a different time.
Third: even if you build it, reaching these owners is hard
Anyone who has sold to small businesses knows how difficult these owners are to reach and how little time they have. They spend their days and nights handling customers and paperwork. Even when you reach them, they are not technical users. Setup must be fast and the payoff immediate, or owners will not try the product, let alone use it daily.
The founders had relevant experience. At Robinhood, Pelle's team worked obsessively to eliminate nearly all manual review from account opening, becoming one of the first brokerages to do it. His co-founder, Frédéric Renken, was the first product hire at Superhuman, where the team scrutinized every point of friction in a new user's first experience.
Their unglamorous playbook: do the job, then install the product in person
How did they make it work? The answer has little to do with models. They embraced two labor-intensive tactics Silicon Valley had long dismissed. Both can be traced to essays Paul Graham wrote more than a decade ago.
The usual approach
Hire consultants or interview owners over coffee
In 2012, Paul Graham wrote about the Yiddish word schlep: exhausting, tedious work nobody wants to do. His observation was that the best startup ideas are often hiding in plain sight. The drudgery makes founders overlook them before they even register. He called this schlep blindness. Stripe is the classic example. Everyone knew online payments were painful, yet founders kept building recipe websites instead.
Their approach
Work inside practices for months and do the job themselves
They reconciled millions of dollars in insurance payments, submitted thousands of insurance claims, and billed hundreds of patients. They did it for months, not a weekend. That experience showed them exactly which actions consumed those 200 hours—and gave them the confidence to claim their product was an order of magnitude better than alternatives.
The usual approach
"Great, I'll send you a link"
In Do Things that Don't Scale, Paul Graham described a Stripe tactic known inside YC as the Collison installation. Other founders would ask, "Would you like to try our beta?" If the answer was yes, they would promise to send a link. The Collison brothers did not wait. They said, "Give me your laptop," and installed it on the spot.
Their approach
Fly out and install it for the first 100 practices
From Florida to Kansas to Oregon, they stood behind owners and watched them connect their practice management systems, bank accounts, and data sources one by one. Only after setting up the first 100 practices could they make the process self-service.
Lassie's two co-founders. The stack of papers on the windowsill and the forms spread across the desk are the materials they handled every day for months. Image: a16z News.
700 practices, 49 states, and $10 million in annualized revenue
What did those two unglamorous methods produce? As of June 3, 2026, the company reported these figures.
The last two figures cross-check: 250,000 hours ÷ 700 practices ÷ 12 months ≈ 29.8 hours per practice per month, matching the stated average of 30 hours. Growth has come mainly from word of mouth and customer referrals, adding dozens of practices each month. One customer told them, "You saved my marriage."
The $35 million Series A was led by a16z's Alex Rampell and Olivia Moore. The announcement puts the market at roughly 160,000 dental practices in the US. Pelle uses a broader figure of 500,000 medical practices in his account.
Today, the product automates two steps in the payment flow
Lassie's product page lists three functions. Their position in the earlier payment flow is straightforward.
1 · Enrolls electronic payments
Lassie enrolls the practice in insurers' electronic-payment systems, removing paper checks and postal delays.
2 · Reconciles EFTs
It matches every electronic funds transfer in the bank account to the correct insurer, patient, and insurance claim.
3 · Posts payments
It posts each reconciled item back to the practice management system, keeping the ledger current.
The two highlighted steps are automated today
Record care
1Submit claim
2Insurer pays
3Reconcile
4Bill patient
5Appeal denial
6The investment announcement also says Lassie reads insurance claims and flags those that require action—the first half of step 6. "Let small businesses run themselves" is the long-term goal. Reconciling and posting insurance payments for dental practices is the product's current scope.
a16z describes it the same way. Dental is the first market because the pain is acute, the workflow is structured and repetitive, and the dollar amounts are meaningful. The larger ambition extends beyond dentistry, but that comes later.
Two nearby figures can look like the same claim
Pelle says the system aims to replace "$200,000 a year in administrative labor." The actual result reported in the same article is an average of 30 hours recovered per practice each month.
Placed side by side, those figures can make it sound as though the full $200,000 has already been saved. At typical US wage rates for dental administrative staff, 30 hours a month represents several hundred to roughly $1,000 in monthly labor costs—or several thousand to a little over $10,000 a year. $200,000 is the ceiling for the whole category of work. 30 hours is how far the product has reached today. There is still a large gap between them.
One more calculation: $10 million in annualized revenue ÷ 700 practices ≈ $14,300 per practice per year, or roughly $1,190 per month. This is our back-of-the-envelope estimate from two public figures, not an official price. Lassie has not published pricing, and actual rates may vary by practice size.
Two issues go unmentioned throughout Pelle's account: who is liable when the AI files an insurance claim incorrectly, and how the system meets HIPAA requirements for patient data. For a product that directly handles medical billing and patient information, these are the two most important unanswered questions. The article says only that the work must be done correctly, and we found no public answers.
What customers pay for is not quite what the founder pitches
Behind the headline numbers, the real reason customers pay is slightly different. You can see it only by comparing Pelle's account with the investment announcement published the same day. Each identifies a different primary benefit.
The founder's pitch
Give doctors their evenings back
"Doctors can see twice as many patients, get home on time, and actually take vacations." This version centers on time and quality of life. Its examples are Dr. Ed Zuckerberg doing paperwork at 11 p.m. and the customer who said, "You saved my marriage."
What customers told investors
Recover money that used to slip away
According to a16z, customers said the biggest benefit was recovering underpayments, denials, and missed insurance claims that previously slipped through. That mattered more than completing the work faster. It maps to step 6 in the payment flow: claims nobody identified used to become lost revenue.
Saving time is a feeling. Recovering lost money appears on the ledger. The first makes owners happy; the second gives them a measurable reason to renew every month.
The same announcement draws a hard line around the product: Lassie is not a copilot. A copilot would create more work for practice staff to review. Lassie's goal is to finish the job directly.
Five tactics from this case are directly reusable
Set Lassie itself aside. What remains useful about its approach? Each of the five lessons below follows from the evidence above—not from a vague claim that "vertical AI has potential."
1 · Do the job for several months; do not merely research it
Research tells you there is "too much paperwork." Doing the work tells you the bottlenecks are steps 4 and 6. The founders reconciled millions of dollars in payments, submitted thousands of insurance claims, and billed hundreds of patients before they understood exactly which actions consumed those 200 hours. That level of detail determines where the product should enter the workflow. Ask yourself: have I personally run this industry's process from beginning to end?
2 · Choose the drudgery others avoid, then filter industries with four tests
Paul Graham's idea of schlep blindness has a practical implication: the less anyone wants to touch a problem, the less competition it attracts—and the harder a solution becomes to copy once built. Anthropic's distribution chart can serve as a map of markets where few people are working. To choose among them, use a16z's four reasons for selecting dental: acute pain, structured workflows, repetitive actions, and meaningful transaction values.
3 · After delivery, the customer's task list should get shorter
a16z positions Lassie as something other than a copilot because a copilot creates more work for the practice to review. This is a direct test for your own product: after installation, does the user have one less job to do, or one more dashboard to monitor? The former can replace labor budget. The latter belongs in the tools budget.
4 · Install the first 100 customers by hand; what you are installing is your own understanding
They pushed Stripe's tactic to the limit, installing the product practice by practice from Florida to Kansas to Oregon. The return was not the revenue from those 100 customers. It was learning exactly where a nontechnical user gets stuck, so customer 101 could connect the system alone. Self-service grows out of hands-on service.
5 · Ask customers how they describe you to other people
The founder says Lassie gives doctors their evenings back. Customers tell investors it recovers money they used to miss. Both are true, but only the latter is a measurable financial result—and a reason to renew every month. Once a product has traction, the words customers use to describe it are often more valuable than the positioning copy the company writes for itself.
The saved time did not turn into layoffs
One obvious question remains: what happens to administrative staff after dozens of hours of work disappear?
Pelle invokes an old economic idea: the lump of labour fallacy. It describes the mistaken belief that the total amount of work in the world is fixed, so every additional task performed by a machine must remove one from a person.
After observing 700 practices, he says he is convinced this is a fallacy. Owners used the time to expand their practices, improve the patient experience, and do work that had always been more valuable. That is the company's account, unsupported by independent data, though it points in the same direction as another public study.
Lassie says its next two jobs are spreading the message faster—millions of owners still do not know this is possible—and making installation simple enough for any owner to complete alone. After that comes going deeper: doing more work and connecting to more of the tools a business already uses.
Pelle's account ends with a hiring pitch.
A note on the figures: the 700-practice count cited here is from June 3, 2026. At publication, Lassie's homepage said "2,500+ doctors," while its company page still said "700+ practices." Doctors and practices are different units—a practice typically has several doctors—so the two figures cannot be compared directly.
He worked in dental practices for months, then built AI used by 700 of them
Lassie co-founder's account, read alongside a16z's investment announcement: the operating playbook behind a $35 million round, explained visually on one page.
↓ Read it in one page · Includes an animated chart
On June 3, 2026, a16z announced that it had led a $35 million investment in Lassie. The same day, it published an account by co-founder Steijn Pelle. The story began when Pelle's own dentist told him the practice spent 200 hours every month on administrative paperwork—the equivalent of one full-time employee doing nothing but paperwork all month.
After leaving Robinhood, Pelle spent several months working inside dental practices. A typical day began with downloading a PDF containing hundreds of insurer payments, then entering them one by one into the practice's system. Next came printing a 40-page list, checking every balance, and generating patient bills.
The US dental-practice payment workflow, reconstructed from public sources. An insurance claim is the practice's request for payment. Once money arrives, staff must manually match hundreds of payments to hundreds of claims. That is where most of the 200 hours go.
AI can already do sophisticated work, so why are people still entering these payments manually? In February 2026, Anthropic analyzed nearly 1 million agent calls on its API—AI programs that can use tools and finish tasks—and classified them by industry.
Half of all agent activity is software engineering. The rest is spread across 16 industries, none above 9%. Anthropic's explanation: code can be run to verify whether it works. In healthcare, law, and finance, checking the AI's work requires nearly as much expertise as doing the work itself, so trust develops slowly.
Healthcare's 1.0% is easy to misread. It marks a market that has barely opened.
The hard part was not the model. A dental practice connects to dozens of insurer portals, several claims clearinghouses, one practice management system, and one bank account. In Steijn Pelle's words, each operates in its own way and breaks on its own schedule. Their answer was two forms of manual work Silicon Valley had dismissed for years.
"Great, I'll send you a link"
"Give me your laptop" → Fly out and install it
Over those months, the founders reconciled millions of dollars in insurance payments, submitted thousands of insurance claims, and billed hundreds of patients. That is how they learned exactly which actions consumed those 200 hours. They personally installed the first 100 customers from Florida to Kansas to Oregon. Only then did they understand how customer 101 could connect the system alone. The two ideas come from Paul Graham's schlep—tedious work nobody wants to do—and Stripe's early on-site installations.
As of June 3, 2026, those two methods had produced the following results:
The last two figures agree: 250,000 hours ÷ 700 practices ÷ 12 months ≈ 29.8 hours per practice per month. All figures come from Lassie and a16z and have not been independently verified.
Match every bank transfer to the insurer, patient, and insurance claim
Post reconciled results back to the practice management system
For denial appeals, Lassie only flags claims that need action
There is no evidence beyond dental; autonomous small businesses remain the ambition
- Pelle says the goal is to replace "$200,000 a year in administrative labor." The delivered result is 30 hours recovered per practice per month—worth several thousand to a little over $10,000 a year at typical US dental-administration wages. $200,000 is the ceiling for the whole category; 30 hours is the product's current reach. The nearby figures are easy to confuse.
- The article never addresses who is liable if the AI files an insurance claim incorrectly or how it satisfies HIPAA requirements for patient data.
- 700 practices is the June 3 figure. Lassie's homepage now says "2,500+ doctors," while its company page still says "700+ practices." Doctors and practices are different units and cannot be compared directly.
The article's most valuable insight appears only when the founder's account is compared with the investment announcement published the same day: each side identifies a different primary benefit.
Give doctors their evenings back: see twice as many patients, get home on time, and actually take vacations. The examples are Dr. Ed Zuckerberg doing paperwork at 11 p.m. and the customer who said, "You saved my marriage."
Recover underpayments, denials, and missed insurance claims that used to slip away. That mattered more than completing the work faster. It maps to the final step in the workflow: claims nobody identified became lost revenue.
Saving time is a feeling. Recovering lost money is measurable—and gives customers a reason to renew each month. The same announcement draws a hard line around the product: Lassie is not a copilot, an assistant that offers advice and waits for a human decision. A copilot would create more work for practice staff to review.
then enter them one by one.
Next, check a 40-page list and bill patients.
to hundreds of claims by hand.
One full-time employee
handling only paper
Why not this?
"Great, I'll send
you a link."
Get home on time.
Actually take vacations.
- × Practices still record care, submit claims, and bill patients
- × For appeals, it only flags claims needing action
- × No evidence yet beyond dental
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